Electrically-operated drop-hammer.



J. D. MACDONALD. ELEGTRICALLY OPERATED DROP HAMMER.

APPLICATION FILED JUNE 4. 1913.

1 1 22,962. Patented Dec. 29, 1914.

J. D. MACDONALD.

ELECTRIGALLY OPERATED DROP HAMMER.

APPLICATION FILED JUNE 4,1913.

1 1 22,962, Patented Dec. 29, 1914.

Z SHEETS -SHEET 2. 5

@lmoentoz JOHN D. MACDONALD, OF PITTSBURGH, PENNSYLVANIA.

ELECTRICALLY-OPEBATED DROP-HAMMER.

Application filed June 4, 1913.

To all whom it may concern:

Be it known that I, JOHN D. MACDONALD, a citizen of the United States, residing at Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented new and useful Improvements in Electrically- Operated Drop-Hammers, of which the following is a specification.

This invention relates to improvements in drop hammers and has particular application to an electrically operated hammer.

In carrying out the present invention, it is my purpose to provide an electrically operated drop hammer wherein the ram or head will be reciprocated electrically and wherein the flow of current to the propelling devices may be both manually and automatically controlled so that the ram or head may be reciprocated at any desired speed.

It is also my purpose to provide an electrically operated hammer wherein the ram or head proper will control the flow of current to the governor controlling the automatic operation of the hammer so that the propelling devices will be energized by the current in accordance with the position of the ram or head whereby when the head or ram is down the respective propelling devices that elevate the same will be energized, while when the head is elevated the respective dei'iccs that force the head downwardly will be brought into service.

Furthermore, I aim to provide a hammer of the class described wherein the propelling devices will be preferably in the form of solenoids, certain of which when energized serve to force the hammer downwardly and cooperate with the remaining solenoids to elevate the ram or head after the latter has reached the limit of its downward movement, the circuit of the solenoids being broken automatically when the ram is down so that when the circuit is again closed all of such solenoids will cooperate to elevate the head or ram.

With the above and other objects in view, the invention consists in the construction, combination and arrangement of parts hereinafter set forth in and falling within the scope of the claims.

In the accompanying drawings; Figure 1 Specification of Letters Patent.

Patented Dec. 29, 1914.

Serial No. 771,748.

is a vertical sectional View through the easing and propelling devices. Fig. 2 is a view in elevation of a portion of the ham mer. Fig. 3 is a diagrammatic view.

Referring now to the accompanying drawings in detail, the numeral 1 designates a vertical casing composed of some suitable material and adapted to be secured in some suitable manner to the upper portion of the hammer, furthermore, such casing hav ng the upper end thereof open and eqnlpped with a removable cover 2 formed with an aperture 3 coaxial with an aperture 4 in the lower wall of the casing. The inner wall of the aperture 4 in the lower wall of the casing is preferably screw threaded and receives one end of a vertical tube 5 formed of brass or other non-magnetic material and having the upper open end thereof disposed within the aperture 3 in the cover 2 so that the tube will be held concen' trically of the vertical axis of the casing. Surrounding the tube 5 and disposed with in the casing 1 are superposed solenoids 6, 6 and 7, 7, the lowermost solenoid 7 resting upon wooden blocks 8 or other appropriate supports seated upon the lower wall of the casing.

The numeral 9 designates the ram or head constructed of suitable metal or the like and equipped with an upwardly projecting stem 10 slidably disposed within the tube or sleeve 5 and are preferably formed of bronze or analogous non-magnetic material, a core 11 of soft steel or the like magnetizable material being suitably connected to the free end of the stem 10 and disposed within the tube under the influence of the solenoid magnets 6, 6 and 7 7.

Suitably fastened to the frame of the hammer adjacent to and parallel with the path of movement of the ram or head 9 is a slab 12 and suitably fastened to the face of the slab in proximity to the head or ram is a vertical strip of metal composed of a number of sections 13, 14, 15 and 16 insulated one from the other, and a continuous metallic strip 17 disposed in parallelism therewith and insulated therefrom. In the present instance, the end sections 13 and 16 are relatively short as compared with the innermost sections 14 and 15. The face of the ram or head 9 confronting the sectional and continuous strips is formed adjacent to the upper end thereof with a recess in which is mounted for sliding movement a brush 18 normally held in engagement with the continuous and sectional strips under the action of a coiled expansion spring disposed Within the recess at the rear of the brush, such brush serving to bridge the continuous strip and the sections of the other strip.

A controller is indicated at 19 and in the present instance, comprises a lever 20 fulcrumed at one end as at 21 for swinging movement and carrying a contact adapted to engage any one of a number of contacts 22, 23, 21 and. 25 disposed in an arc struck from the fulcrum point of the lever 20 so that when the latter is swung the contact carried thereby will engage the contacts 22, 23, 2 1 and 25. Terminally connected to the lever 20 is a lead wire 26, while leading from the contact 2 1 is a conductor 27 connected to one side of the solenoids 7, 7. A second conductor 28 has one terminal thereof tapped onto the contact 23 and is connected to one side of the solenoids 6, 6, the free terminals of the solenoids 6, 6 and 7, 7 being connected to the lead wire 29. The latter and the lead wire 26 being connected up to a suitable source of electrical energy, such for instance, as a generator.

Leading from the contact point 22 is a conductor 30 having the free terminal thereof tapped onto the continuous strip 17.

The numeral 31 designates a governor composed, in the present instance, of solenoid magnets 32, 33 disposed in horizontal alinement, and a core 34 having the 0ppo site ends thereof extending into the magnets and adapted to be moved to one side or the other according to which solenoid is energized. One terminal of the solenoid 32 is connected by means of a wire 35 with the section 13 of the sectional strip, while the opposite terminal of such solenoid is connected to the conductor 27 by way of a Wire 36. Disposed at opposite sides of the core 34 of the governor are the contacts of pairs 37, 38 and 39, while suitably secured to the core is a bridging strip 40 adapted to bridge 7 the contacts of the pair 37 or the pair 38 according to the movement of the core, a second bridging strip 41 being also carried by the core and spaced apart a suitable distance from the strip 40 to bridge the contacts of the pair 39. One contact of each pair 37, 38 is connected by way of a wire 42 with the section 14 of the sectional strip, while the remaining contact of the pair 37 is tapered onto the wire 36, the remaining contact of the pair 38 being connected to the conductor 28 by way of a Wire 13. One of the contacts of the pair 39 is electrically connected with the section 15 of the sectional strip by way of a wire 44, while the remaining contact of such pair is connected to the wire 36 by Way of a wire 45. The solenoid 33 has one terminal connected to the bottom section 16 of the sectional strip through the medium of a wire 46, while the free terminal thereof is tapped onto the wire with the respective contact of the pair 39.

From the foregoing description taken in connection with the accompanying drawings, the construction and mode of operation of my invention will be readily apparent. When the ram 9 is in elevated posi tion as shown in Fig. 1, the brush 18 bridges the continuous metallic strip 17 and the section 13 of the sectional strip so that when the lever 20 is in engagement with the contact 22 current flows through the solenoid 32 and the propelling solenoids 7, 7, the current flowing from one side of the generator through the lead wire 26, lever 20, conductor 30, continuous strip 17, brush 18, section 13 of the sectional strip, conductor 35, the coil of the solenoid 32, wire 36, the respective portion of the conductor 27, the lower propelling solenoids 7, 7 and thence back to the other side of the generator by way of the lead 29. The solenoid 32 being energized, the core 34 is drawn to the left with the result that the bridging strip 10 bridges the pair of contacts 37. As the pro pelling solenoids 7, 7 are energized they exert a pull. upon the core 11 and so force the ram downwardly and as the rain moves down the brush 18 rides off of the section 13 and onto the section 1 1 of the sectional strip thereby reestablishing the circuit through the propelling solenoids 7, 7 by way of the wire 4-2, the pair of contacts 37,

37 and the wire 36, thus cutting the solenoid 32 out of the circuit. When the brush 18 rides off of the section 14: and onto the section 15, incident to the downward movement of the ram or head, the circuit to the propelling solenoids 7, 7 is broken as is readily apparent and the ram continues down under its own momentum. When the head or ram reaches the limit of its downward movement, the brush 18 is in engagement with the lower section 16 of the sectional strip and so bridges the continuous strip 17 and the section 16 whereby current flows from the lead 26 through the lever 20, contact 22, conductor 30, strip 17, section 16, wire 46, solenoid 33, wire 45 and respective portion of the conductor 28, through the propelling solenoids 6, 6 and thence back to the generator by way of the lead 29. Thus, the circuit of the pro pelling solenoids 6, 6 is reestablished and the latter again act upon the core 11 to elevate the head or ram. The current flowing through the coil of the solenoid 33 of the governor 31, energizes such solenoid with the effect that the core 34 is drawn to the right of Fig. 1 thereby causing the bridging strip 41 to bridge the pair of contacts 39 and the bridging strip 40 to bridge the pair of contacts 38. As the ram 9 moves upwardly under the lifting action of the solenoids (3, 6, the brush 18 rides off of the section 16 and onto the section 15 thereby cutting the coil of the solenoid 33 out of the circuit and closing the circuit through the solenoids 6, 6 by way of the wire 44, contacts 39, and bridging strip 4-1, the wires a?) and 28. Succeeding the closing of the circuit through the contacts 39 and the bridging strip 40, the core 11 has entered the lower magnet of the pair 6, 6 and the brush 18 disengaged the section 15 and engaged the section Ll of the sectional strip so that the circuit to the upper propelling magnets 6, 6 remain closed, the current flowing from one side of the source of energy through the lead wire 26, lever 20, contact 22, wire 30, continuous strip 17, section 11, wire d2, contacts 38 and bridging strip 40, wire -13, respective portion of the conductor 28, the coils of the solenoids 6, 6 and thence back to the other side of the generator by way of the lead 29. Thus, the ram or head is lifted to its highest point and the brush 18 moved onto the section 13 cf the sectional strip thereby breaking the circuit through the upper set of propelling magnets and reestablishing the circuit through the lower set of propelling magnets whereby the above operation is repeated.

The above operation takes place only when the lever 20 is in engagement with the contact 22 and when the lever in this position, the machine is rendered automatic in action and takes care of itself, the governor 31 controlling the flow of current to the various propelling magnets and conse quently the reciprocatory movement of the head or ram.

The manual control of the various propelling magnets is effected by engaging the lever 20 with one or the other of the contacts Q3 and 24. Thus, when the lever 20 is in engagement with the contact 23 the circuit is closed to the upper set of propelling magnets 6, 6, current flowing from one side of the source of energy through the lead wire 26, lever 20, contact 2i, conductor 28, the coils or the solenoids 6, 6 and thence hack to the other side of the source by way of the lead 29. ()n the other hand, when the lever 20 is in engagement with the con tact 2 1, the current flows through the coils of the lower set of propelling magnets 7, 7 and the lead wire 26 through the conductor 27, the coils of the solenoids and thence back to the source by way of the lead 29. It will be observed by manipulating the lever 20 back and forth over the contacts 23 and 24, the ram or head may be elevated and lowered slowly or at any desired speed.

Vvhen it is desired to cut the machine out of service, the lever 20 of the controller is thrown onto the contact point 25 which latter is dead.

\Vhile I have herein shown and described one preferred form of my invention by way of illustration, I desire to have it understood that I do not limit or confine myself to the precise details of construction herein described and delineated, as modification and variation may be made within the scope of the claims without departing from the spirit of the invention.

The casing 1 is preferably filled or partially filled with an oil so that overheating of the solenoid magnets will be eliminated.

I claim:

1. In an electrically operated hammer, a ram, electroresponsive devices for elevating said ram, electroresponsive devices for forcing said ram downwardly, a source of energy, an electromagnetic device connected in circuit with said first electroresponsive devices, an electromagnetic device connected in circuit with said second-named electroresponsive devices and designed to act in a direction reverse to the first-mentioned electromagnetic device, a core under the control of said electromagnetic devices, a bridging strip carried by said core, a pair of contacts disposed in the path of movement of said bridging strip and adapted to be bridged thereby in the movement of the core under the influence of said first electromagnetic device, a second bridging strip connected with said core, a pair of contacts adapted to be bridged by said last bridging strip in the movement of the core under the influence of said first electromagnetic device, a pair of contacts adapted to be engaged by said last bridging strip in the movement of the core under the influence of the second-named electromagnetic device, a commutator parallel with the path of movement of said ram and comprising a continuous conducting strip and a sectional. conducting strip parallel with the first strip and having the sections thereof insulated from the continuous strip and from one another, a connection between said continuous strip and one side of said source of energy, a connection between the upper section of said sectional strip and said second-named electroresponsive devices including in series said second-named electromagnetic device, a connection between the next adjacent section of said strip and said second-named electroresponsive devices including in series the thirdnamed pair of contacts and between the lastmentioned section of the strip and said first electroresponsive devices including in series, said second-named pair of contacts, a con nection between the third section of said sectional strip and said firstanentioned electroresponsive devices including in series the first-named pair of contacts, a connection between the last section of said strip and said first-mentioned electroresponsive devices including in series the first-mentioned electromagnetic device, means carried by said ram and riding over said strips to connect the sections of said sectional strip successively with the continuous strip, and a connection between the free terminals of the electroresponsive devices and the remaining side of said source of energy.

2. In an electrically operated hammer, a ram, electroresponsive devices for elevating said ram, electroresponsive devices for forc- -ing said ram downwardly, a source of energy, an electromagnetic device connected in circuit with said first electroresponsive devices, an electromagnetic device connected in circuit with said second-named electroresponsive devices and designed to act in a direction reverse to the first-mentioned electromagnetic device, a core under the control of said electromagnetic devices, a bridging strip carried by said core, a pair of contacts disposed in the path of movement of said bridging strip and adapted to be bridged thereby in the movement of the core under the influence of said first electromagnetic device, a second bridging strip connected with said core, a pair of contacts adapted to be bridged by said last bridging strip in the movement of the core under the influence of said first electromagnetic device, a pair of contacts adapted to be engaged by said last bridging strip in the movement of the core under the influence of the second-named electromagnetic device, a commutator parallel with the path of movement of said ram and comprising a continuous conducting strip and a sectional conducting strip parallel with the first strip and having the sections thereof insulated frcm the continuous strip and from one another, a connection between said continuous strip and one side of said source of energy, a connection between the upper section oi said sectional strip and said second-named electroresponsive devices including in series said second-named electromagnetic device. a connection between the next adjacent section of said strip and said second-named (flGCtll)I'CSPUIlSlYO devices including in series the third-named pair of contacts and between the last-mentioned section of the strip and said first electroresp vnsive devices including in series said second-named pair of contacts. a connection between the third section of said sectional strip and said firstmentioned lB('tl'0l0S])(lIiSlVtf devices includ ing in series the first-named pair of contacts, a connection between the last section of said strip and said first-mentioned clectrore sponsive devices including in series the firstmentioned electromagnetic device, a spring pressed brush carried by said ram and riding over said strips to connect the sections of said sectional strip successively with the continuous strip, and a connection between the free terminals of said electroresponsive devices and the remaining side of said source of energy.

3. In an electrically operated hammer, a ram, electroresponsive devices for elevating said ram, electroresponsive devices for forcing said ram downwardly, a source of energy, an electromagnetic device connected in circuit with said first electroresponsive devices, an. electromagnetic device connected in circuit with said second-named electroresponsive devices and designed to act in a direction reverse to the first-mentioned electrcmagnetic device, a core under the control of said electromagnetic devices, a bridging strip carried by said core, a pair of contacts disposed in thepath of movement of said bridging" strip and adapted to be bridged thereby in the movement of the core under the influence of said first electromagnetic device, a second bridging strip connected with said core, a pair of contacts adapted to be bridged by said last bridging strip in the movement of the core under the influence of said first electromagnetic device, a pair of contacts adapted to be engaged by said last bridging strip in the movement of the core under the influence of the second-named electromagnetic device, a commutator parallel with the path of movement of said ram and comprising a continuous conducting strip and a sectional conducting strip parallel with the first strip and having the sections thereof insulated from the continuous strip and from one another, a connection between said continuous strip and one side of said source of energy, a connection between the upper section of said sectional strip and said second-named electroresponsive devices including in series said secondnamed electromagnetic device, a connection between the neXt adjacent section of said strip and said second-named electroresponsive devices including in series the third-named pair of contacts and between the last-mentioned section of the strip and said first electroresponsive devices ineluding in series, said second-named pair of contacts, a connection between the third section of said sectional strip and said firstmentioned electroresponsive devices including in series the first-named pair of contacts, a connection between the last section of said strip and said first-mentioned electroresponsive devices including in series the first-mentioned electromagnetic device, means carried by said ram and riding over said strips to connect the sections of said sectional strip successively with the continuous strip, a connection between the free terminals of the electroresponsive devices and the remaining side of said source of energy, and a controller in the connection between said continuous strip and said In testimony whereof I afiix my signature source of energy whereby the commutator 1n presence of two wltnesses.

and electromagnetic devices may be out out JOHN D. MACDONALD. of service and said first and second-named \Vitnesses:

electroresponsive devices connected with the DOUGALD A. MACDONALD,

source of energy alternately. GEORGE E. HARTENSTEIN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G." 

